A quick Google search reveals that there is indeed a salary differential -- this is for FS, but the story in professional services is probably similar:"Whereas four years ago, you may have seen a 30-40% differential in pay when compared to London, now the gap is only 15-20% - and candidates have the benefits of a much better work life balance. Many Scots who have trained in London are now returning here to continue their careers leaving what many perceive as the gruelling pace of London behind. We are also seeing an influx of candidates from European locations such as Amsterdam, Luxemburg and Scandinavia who are choosing Scotland above London as their preferred route to gaining international experience."www.s1jobs.com/recruiterprofiles/parker/ppb-salary-survey.pdf
